WIP checkpoint. Code that builds.

Use Option<VMTrampoline> which should be ffi-compatible.

Put the register_signature and lookup_signature functions back on the Engine.

lib/api/src/externals/function.rs

@@ -10,18 +10,9 @@ use std::cell::RefCell;
 use std::cmp::max;
 use std::fmt;
 use wasmer_vm::{
-    raise_user_trap,
-    resume_panic,
-    wasmer_call_trampoline,
-    Export,
-    ExportFunction,
-    VMCallerCheckedAnyfunc,
-    VMContext,
-    VMDynamicFunctionContext,
-    VMFunctionBody,
-    VMFunctionKind,
-    VMSharedSignatureIndex,
-    VMTrampoline,
+    raise_user_trap, resume_panic, wasmer_call_trampoline, Export, ExportFunction,
+    VMCallerCheckedAnyfunc, VMContext, VMDynamicFunctionContext, VMFunctionBody, VMFunctionKind,
+    VMSharedSignatureIndex, VMTrampoline,
 };
 
 /// A function defined in the Wasm module
@@ -104,7 +95,7 @@ impl Function {
                 kind: VMFunctionKind::Dynamic,
                 vmctx,
                 signature: ty.clone(),
-                trampoline: std::ptr::null_mut(),
+                trampoline: None,
             },
         }
     }
@@ -154,7 +145,7 @@ impl Function {
                 kind: VMFunctionKind::Dynamic,
                 vmctx,
                 signature: ty.clone(),
-                trampoline: std::ptr::null(),
+                trampoline: None,
             },
         }
     }
@@ -196,7 +187,7 @@ impl Function {
                 vmctx,
                 signature,
                 kind: VMFunctionKind::Static,
-                trampoline: std::ptr::null(),
+                trampoline: None,
             },
         }
     }
@@ -250,7 +241,7 @@ impl Function {
                 kind: VMFunctionKind::Static,
                 vmctx,
                 signature,
-                trampoline: std::ptr::null(),
+                trampoline: None,
             },
         }
     }
@@ -314,7 +305,7 @@ impl Function {
         if let Err(error) = unsafe {
             wasmer_call_trampoline(
                 self.exported.vmctx,
-                *func.trampoline,
+                func.trampoline,
                 self.exported.address,
                 values_vec.as_mut_ptr() as *mut u8,
             )
@@ -364,9 +355,10 @@ impl Function {
     }
 
     pub(crate) fn from_export(store: &Store, wasmer_export: ExportFunction) -> Self {
+        let trampoline = wasmer_export.trampoline.unwrap();
         Self {
             store: store.clone(),
-            definition: FunctionDefinition::Wasm(WasmFunctionDefinition { trampoline: wasmer_export.trampoline }),
+            definition: FunctionDefinition::Wasm(WasmFunctionDefinition { trampoline }),
             exported: wasmer_export,
         }
     }

lib/api/src/native.rs

@@ -69,6 +69,7 @@ where
             vmctx: other.vmctx,
             signature,
             kind: other.arg_kind,
+            trampoline: None,
         }
     }
 }
@@ -88,6 +89,7 @@ where
                 vmctx: other.vmctx,
                 signature,
                 kind: other.arg_kind,
+                trampoline: None,
             },
         }
     }

lib/api/src/types.rs

@@ -78,6 +78,7 @@ impl ValFuncRef for Val {
             // are converted to use the trampolines with static signatures).
             kind: wasmer_vm::VMFunctionKind::Static,
             vmctx: item.vmctx,
+            trampoline: None,
         };
         let f = Function::from_export(store, export);
         Val::FuncRef(f)

lib/engine-native/src/artifact.rs

@@ -338,7 +338,8 @@ impl NativeArtifact {
             metadata,
             library: None,
             finished_functions: finished_functions.into_boxed_slice(),
-            finished_function_call_trampolines: finished_function_call_trampolines.into_boxed_slice(),
+            finished_function_call_trampolines: finished_function_call_trampolines
+                .into_boxed_slice(),
             finished_dynamic_function_trampolines: finished_dynamic_function_trampolines
                 .into_boxed_slice(),
             signatures: signatures.into_boxed_slice(),
@@ -390,11 +391,14 @@ impl NativeArtifact {
         }
 
         // Retrieve function call trampolines
-        let mut finished_function_call_trampolines: PrimaryMap<SignatureIndex, VMTrampoline> = PrimaryMap::with_capacity(metadata.compile_info.module.signatures.len());
+        let mut finished_function_call_trampolines: PrimaryMap<SignatureIndex, VMTrampoline> =
+            PrimaryMap::with_capacity(metadata.compile_info.module.signatures.len());
         for sig_index in metadata.compile_info.module.signatures.keys() {
             let function_name = metadata.symbol_to_name(Symbol::FunctionCallTrampoline(sig_index));
             unsafe {
-                let trampoline: LibrarySymbol<VMTrampoline> = lib.get(function_name.as_bytes()).map_err(to_compile_error)?;
+                let trampoline: LibrarySymbol<VMTrampoline> = lib
+                    .get(function_name.as_bytes())
+                    .map_err(to_compile_error)?;
                 let raw = *trampoline.into_raw();
                 finished_function_call_trampolines.push(raw);
             }
@@ -454,7 +458,8 @@ impl NativeArtifact {
             metadata,
             library: Some(lib),
             finished_functions: finished_functions.into_boxed_slice(),
-            finished_function_call_trampolines: finished_function_call_trampolines.into_boxed_slice(),
+            finished_function_call_trampolines: finished_function_call_trampolines
+                .into_boxed_slice(),
             finished_dynamic_function_trampolines: finished_dynamic_function_trampolines
                 .into_boxed_slice(),
             signatures: signatures.into_boxed_slice(),

lib/engine-native/src/engine.rs

@@ -123,7 +123,6 @@ impl Engine for NativeEngine {
         &self.target
     }
 
-    /*
     /// Register a signature
     fn register_signature(&self, func_type: &FunctionType) -> VMSharedSignatureIndex {
         let compiler = self.inner();
@@ -136,6 +135,7 @@ impl Engine for NativeEngine {
         compiler.signatures().lookup(sig)
     }
 
+    /*
     /// Retrieves a trampoline given a signature
     fn function_call_trampoline(&self, sig: VMSharedSignatureIndex) -> Option<VMTrampoline> {
         self.inner().trampoline(sig)

lib/engine/src/engine.rs

@@ -19,13 +19,13 @@ pub trait Engine {
     /// Gets the target
     fn target(&self) -> &Target;
 
-    /*
     /// Register a signature
     fn register_signature(&self, func_type: &FunctionType) -> VMSharedSignatureIndex;
 
     /// Lookup a signature
     fn lookup_signature(&self, sig: VMSharedSignatureIndex) -> Option<FunctionType>;
 
+    /*
     /// Retrieves a trampoline given a signature
     fn function_call_trampoline(&self, sig: VMSharedSignatureIndex) -> Option<VMTrampoline>;
     */

lib/vm/src/export.rs

@@ -35,8 +35,8 @@ pub struct ExportFunction {
     pub signature: FunctionType,
     /// The function kind (it defines how it's the signature that provided `address` have)
     pub kind: VMFunctionKind,
-    /// Address of the function call trampoline owned by the same VMContext that owns the VMFunctionBody. May be nullptr when FunctionType == Dynamic or vmctx == nullptr.
-    pub trampoline: VMTrampoline,
+    /// Address of the function call trampoline owned by the same VMContext that owns the VMFunctionBody. May be None when FunctionType == Dynamic or vmctx == nullptr.
+    pub trampoline: Option<VMTrampoline>,
 }
 
 /// # Safety

lib/vm/src/instance.rs

@@ -301,7 +301,7 @@ impl Instance {
                     let import = self.imported_function(*index);
                     (import.body, import.vmctx)
                 };
-                let trampoline = self.function_call_trampolines[*sig_index];
+                let trampoline = Some(self.function_call_trampolines[*sig_index]);
                 let signature = self.module.signatures[*sig_index].clone();
                 ExportFunction {
                     address,